Fluid drive



1954 F. K. KUGEL ETAL FLUID DRIVE 6 Sheqts-Sheet 1 Filed Feb. 27, 1950 INVENTORS FRITZ K. KUGEL WILHELM L. 1mm 1 GSCHING Tun MUM, ATTORNEYS g- 1954 F. K. KUGEL ETAL 2,687,657 FLUID DRIVE Filed Feb. 27, 1950 s Sheets-Sheet 2 mvsmons FRITZ K. KUGEL BWYILHELM L. GSCHING ATTORNEYS Aug. 31, 1954 F. K. KUGEL EIAL 2,687,657 I 6 Sheets-Sheet 3 INVENTORS FRITZ .-K. KUGEL -W|LHELM L. GS CHIN G ATTORNEYS 1954 F. K. KUGEL EIAL' FLUID DRIVE Filed Feb. 27. 1950 I 6 Sheets-Sheet 5 INVENTOHS FRITZ K. KUGEL g I LHEL'M L. GSCHING Tm mm ATTORNEYS Aug. 31, 1954 F. K. KUGEL ETAL FLUID DRIVE 2,687,657 Filed Feb. 27. p50 6 Sheets-Sheet s INVENTDRQ FRITZ K. KUGEL gIYILHELM L. GSCHING ATTORNEYS Patented Aug. 31, 1954 2,687,657 FLUID DRIVE Fritz K. Kugel and Wilhelm L. Gsching, H eiden,

heim, Germany, assigngrs to I. M. Vqitl; Maschinenfabrm, Heid'enheim, Germax gy Application February 27, 1950, Serial No. 146,426

16 Claims. (Cl. 749688) t M I t t device Was-sug ested f r ehi le Qnl reth ra w tw nin u po e irl tta-nc t w ls u al Q: 1i I ZQHf 99ntes er Q? a t r ue. com/ether a supl 't an qrdinar s am nsm fiuq an rrange H. 9 a casts whi h are a l I91" it qsto meel j mer dm to 1a.,no e su s i wa thsqlssd ifib w h and e t nrqvid d allowing one or more guide wheelsto rotate. In was suppgsed tp be the 'last mentianed instance the torque converter is used merely-for the starting period. In order h h t@ meet the requirements for a street vehicle, ages created t 4 t a a no m terialismri followed by a mechanical drive with at least Ag pr ung t in ar fi te n nd e a an ed tha U"? PQWFI d ved n m th lmpterwa ttrarasm me anic l y and in art 11 t a M v t a d i ng haf n th veh le, a was not generally adopted. The fact that simgestions did not lead to a satisf other inventprs suggested ,complicated Qonyerterponstruct pr guide wheels prqv mer ous advantages over purely mechanical drives a pumping wheel, a turbine wheel and a figie d jorstreet vehieles is 111 part due to the fact that gui in d iq 1 fi 1 1 1. 5 l d I10 dwma o h o t flefiiqienty Qndt x iqre to anti lie sedufuelttce sumptipn.

M 1.. A th resent i ven on o Pr i e h draulic transmis i n whitish W111 0W som th showmsafiened.draw acks 1 1 hi 1 end the nventi makes m s pf feature tt 7 t t are a t kn w or arelgnown ntcombiw a hydraulic coupl1'ng. It isiather necessary to with gather ieatures, Mpre s peeifigally dra ircuit' s ma tim whe ls combination by add tional device s. tiona'l devices andypossible means arehowever so numerous "and ofso manydifierent types that while this circuit inthe direction of the power transmission is preceded by a planetary gear system. This planetary gear system acts as a power distributor in such a manner that a part of the planetary gear transmission is connected with the power input shaft while another part of the planetary gear system is hooked up with the pumping wheel and a still further part of the planetary gear system is hooked up with the t-ur- It is an object of the present invention to modify this combination, which is known per se and may be termed a hydro-mechanical differential drive, in power transmission path may be interrupted during the operation while simultaneously increasing the input number of revolutions of the other power transmission path. This object may be obtained according to the present invention in two ways: (a) the hydraulic power transmission path may be interrupted and the mechanical part may be driven with increased number of revolutions, or (b) the mechanical part may be interrupted and the hydraulic part may be driven with increased speed. In the first instance the pumping wheel or that part of the planetary gear connected thereto may be arranged so that it can be held stationary by applying a brake thereto, while the turbine wheel is coupled to the output shaft by means of a coupling for instance a free wheel drive which may be automatic or maybe operated selectively. In the second instance the turbine wheel rigidly secured to the output shaft is connected with one part of the planetary gear transmission through an automatic or selectively operable coupling such as a free wheel drive, which part of the planetary gear transmission is additionally provided with a brake. When using a torque converter as hydraulic part of the hydro-mechanical differential drive, in the last mentioned instance such converter is provided with a rotatable guiding apparatus adapted during the operation of the circuit as a torque converter to be held stationary, whereas this guiding apparatus during operation as a coupling and after releasing the brake is allowed to rotate and to couple itself to the turbine wheel. The above mentioned draw-back of such a construction is advantageously modified with the last mentioned device by the increased driving speed during the operation of the coupling.

It has already been suggested, when using such hydro-mechanical difierential drive employing a planetary gear transmission as a power distributor, to arrange the pumping wheel of the converter so that it can be held stationary by a brake while a free wheel drive is arranged be-- tween the turbine wheel and the output shaft. This known construction, however, concerns a so called backward torque converter in which the pumping wheel rotates in a direction opposite to the direction of rotation of the turbine wheel and in which for this purpose a reversing guide wheel is provided. In this known construction the motor is connected with the planetary ring of the planetary gear transmission, while the output shaft is connected with the carrier for the intermediate gears and the sun wheel is connected with the pumping wheel of the converter. Within the range of the starting speed, the pumping wheel is driven in a direction opposite to the direction of rotation of the motor, while the admission to the turbine wheel is effected again in the correct manner via the reversing guide wheel. Such reversing converters have a rather low total efficiency due to the loss incurred during the reversing operation. Furthermore, the introduction of the reversing guide wheel prevents a proper blade arrangement necessary to obtain a sufficient torque conversion.

According to a still further suggestion made heretofore, the motor is again connected with the outer ring of the power distributor of the planetary gear drive. This planetary gear drive, however, is provided with two sets of planetary wheels engaging each other of which one set meshes with the outer ring, while the other set meshes with the sun wheel. Connected to the sun wheel through a free wheel drive is the pumping wheel of a converter, whereas the turbine wheel is connected with the carrier for the intermediate wheels. This solution is unfavorable due to the fact that in view of the greater number of inter-meshing gears a corresponding higher loss is incurred.

The construction according to the present invention shows a material improvement over the heretofore mentioned known constructions inasmuch as the present invention allows the employment of a torque converter of general construction while obtaining a high total efficiency and allowing the application of a simple planetary gear transmission as .power distributor.

Normally, the hydraulic part of the hydromechanical differential drive a torque converter will be employed. However, in specific cases it is also possible to use a hydraulic coupling as hydraulic part of the hydro-mechanical differential drive. This is particularly the case when this hydro-mechanical differential drive is provided with an additional converter the pumping wheel or" which is directly coupled with the input shaft while the turbine wheel is directly coupled with the output shaft. According to a further embodiment of the invention, a converter as well connected with the planetary gear transmission in such a manner that it is possible to drive with power distribution during the employment of the converter as well as during the employment of the coupling.

According to the fixst embodiment using a pumping wheel adapted to be held stationary by a brake and also employing a turbine wheel coupled to the output shaft through a free wheel drive, the starting under application of a converter is effected by operation of the power distributor. The power is then, during the very first starting period, transmitted alone through the converter while with increasing output speed more and more power is transmitted via the mechanical power path, and finally by braking the pumping wheel to maintain the latter stationary and thereby also that part of the planetary gear drive connected thereto, the hydraulic circuit is interrupted while the mechanical part is driven with increased speed. During this operation the turbine wheel detaches itself from the output shaft and comes to a stand-still so that the torque converter is fully detached or made ineffective.

According to the second embodiment mentioned above and comprising a detachable mechanical path, the starting operation with the distributing means is followed by an operation of the hydraulic coupling without distributing means. When using a torque converter and a hydraulic coupling, it will be obvious that with this construction two hydro-mechanical speeds with power distribution are obtained and two purely hydraulic speeds. When using such a drive together with a free wheel drive it is possible by means of a simple additional device, namely the provision of a lockingmechanism for the free braking eificiency.

When using a pumping wheel adapted to be held stationary by application of a brake, in other words when using adetachable hydraulic circuit, will be possible in two Also with this construction an increased braking effect may be obtained by blocking the free wheel drive.

The distributing planetary drive connected to and preceding the hydraulic circuit may be conwheel drive. If, for instance, it is desired also to brake by the converter, abrake is to be substituted for the free wheel drive. This additional arrangement makes possible a third forward or third braking speed.

By combining a planetary gear drive, used as a power distributing transmission, with a torque With a drive according to the present invention the transmission ratio (u) in the distributing drive to the speed ratio 0 of the shiftingpoin great importance.

is to be selected approximately between 0.4 and 1.0. This applies to the range of the usually used gear steps q (maximum speed to shifting speed) of approximately 1.4 to 2.0, the lower values of to the present invention, combination to employ a converter the maximum efiiciency of which lies max. and the of which is located at approximately 0.3 to 0.5. The transconversion and instance the dimensions of the converter are correspondingly greater.

According to a further development of the invention, in order to obtain a rearward speed, there is added a distributing drive comprising two sun wheels and intermediate gears with double rim, and an additional planetary gear set with a sun wheel adapted to be braked. The third set of intermediate gears is so arranged that the wheels are arranged on the same axle as the other intermediate gears, whereas the sun wheel meshing with these intermediate gears is adapted to be braked by a brake drum. The brake for the pumping wheel and the brake for the sun wheel of this third set of intermediate gears may be arranged one within the other in such a manner that they can be equipped with common brake shoes. In such an instance, such brake shoes may be provided with inner and outer linings and may be actuated selectively so that the brake shoes engage the outside of the one brake drum when it is desired to brake the pumping wheel, whereas the brake shoes engage the inner side of the other brake drum when it is intended to brake the sun wheel. In .order to obtain an idling speed and a backward speed and in order to obtain a further materially reduced speed as may be necessary with vehicles subjected to great loads such as busses and heavy trucks, a differential torque drive described above and comprising a planetary distributing drive and torque converter or hydraulic coupling may be further modified according to this invention. To this end an additional planetary drive or a change, gear adapted to be connected to the mechanism by means of a multiple disc coupling may be provided.

In the present description and drawings torque converters are referred to which comprise a converter composed of a single stage pump and turbine wheel and a two stage guiding device. The fluid is centrifugally passed through the pumping wheel and the turbine wheel of said converters, e. g. from the inner portion toward the outer portion thereof. The first stage of the guiding device is passed through by the fluid in axial direction, while the second stage is passed through by the liquid centripetally, i. e. from the outer portion toward the inner portion. It should, however, be noted that also other converters may be used according to the present invention provided the converters meet the respective requirements, Particularly converters with a plurality of stages in the pumping and turbine wheel may be used. The torque converter shown and described in the present invention is a converter of high efficiency adapted to effect a high torque has been proved highly advantageous in practice. It is a matter of course that not all solutions according to the present invention and set forth in the description are of equal advantage with one and the same type of vehicles. Some embodiments set forth in this description are of particular advantage for passenger automobiles, whereas other solutions are of particular advantage in connection with trucks and vehicles on rails.

The invention is illustrated by way of example in the accompanying drawings in which:

Figure 1 diagrammatically illustrates a first embodiment of the invention.

Figure 2 represents a graph illustrating the driving characteristics of a drive according to Figure 1.

Figure 3 illustrates a longitudinal section through the transmission.

Figure 4 is a graph illustrating the various characteristics of the drive according to Figure 3. Figure 5 illustrates a further embodiment of th present invention.

Figure 6 is a still invention,

Figures '7 and 8 represent two further embodiments of the invention according to which the converter is followed by a planetary transmission.

Figures 9 and 10 illustrate two hydro-mechanical transmissions according to the invention in which a planetary transmission with beveled gears is employed.

Figure 11 shows a further invention according to which only one hydraulic circuit and one plural disc coupling is employed for connecting the sun whee1 of the distributing drive with the input shaft.

Figure 12 represents a still further modification of a. two-plane distributing planetary transmission according to which the pumping wheel is connected with a sun whee1 while the output shaft is connected with the carrier for the intermediate gears.

Figure. 13 diagrammatically illustrates a twoplane distributing planetary drive which is driven through a sun Wheel.

Figures 14 to 24 show arrangements similar to those of Figures 1 to 13, however, with the difference that not the hydraulic transmission branch but the mechanical transmission branch Of the differential drive may selectively be made ineffective.

In order to facilitate the understanding of the invention and the comparison between the various embodiments shown in the drawings, all transmissions are shown in such a manner that on the left hand side the input shaft connected to the motor is located, while on the right hand side the output shaft is arranged. Referring now to Figure 1 in particular, the structure shown therein comprises a motor shaft l to which is connected the set of intermediate gears 2 which mesh with the planetary ring 3 and the sun wheel 4. The planetary ring 3 is connected with the intermediate shaft 5 which latter carries the brake drum 6 and the converter pumping wheel 1. The sun wheel 4 i rigidly connected to the output shaft 8, and also connected to the output shaft 8 is the turbine wheel 9 of the converter via free wheel coupling or drive Hi. This free wheel drive or coupling is so arranged that it can effect a power transmission from the turbine wheel to the output shaft if the speed of the output shaft is lower than that of the turbine wheel, whereas, if the speed of the output shaft increases beyond the speed of the turbine wheel, the power transmission is interrupted. G designates the stationary guide wheel or guiding apparatus.

At the instance of starting the output shaft 8 and, therefore, also, the sun wheel 4 are at a stand still. Consequently, the intermediate wheels merely revolve about the teeth of the sun wheel and via the planetary ring 3 drive the pumping wheel 1 with a transmission into high. Due to the high speed, the pumping wheel I receives a great torque and thereby loads the motor so that the latter during the starting period has its number of revolutions reduced. The pumping wheel thus transmits its motion via the turbine wheel 9 and coupling Hi to the output shaft 8. 'At this stage the power will be transmitted purely hydraulically. Due to the torque transmitted from the turbine wheel to .the output shaft, the

further embodiment of the modification of the latter and thus, also, the sun wheel 4 begins to rotate and the vehicle begins to move.

ential drive, the brake l l is applied, thereby holding the planetary ring 3 and the pumping wheel! stationary. As a result thereof, the sun wheel is driven with increased speed inasmuch as the intermediate gears merely roll over the teeth of the planetary ring. In addition thereto, the conpond the speed of the turbine wheel.

Figure 2 represents a graph illustrating the driving characteristics of thesimple two speed drive according to Figure 1. In this showing, however, the motor speed is not stated in a cerforce l2, the motor speed I3 and the efliciency M of the transmission, the mechanical loss and the power transmission branch.

As will be seen from the graph, when starting with the throttle open, the power at disposal is this pulling force in contrast to the driving conditions of a gear change drive is definitely available and for any desired time.

Gen-

erally, these driving features and power outputs of the difierential transmission meet the requirements of a motor vehicle, provided arrangements are made for an idling speed and a rearward ures 3 and 4. The arrangement according to Figure 3 shows a two plane distributing planetary Meshing 5 and it are the interratus 25 and a double jacket 21 for a cooling liquid. Associated with the transmission shaft i7 is a three plane planetary gear combination 28 that tion is characterized by a materially higherstartspeed is effected by changing the filling of the ing' pulling power and greater efficiency. Consehydraulic circuits, whereas the other speeds are quently, such transmission uses less fuel within made effective by applying and releasing the the starting range and at low driving speeds and brakes. If only one converter is available and does so with a simplified construction. no hydraulic coupling and if the converter is Referring now'to Figure 5, this figure shows permanently filled, a shiftable coupling isto be a transmission in which the hydraulic transmisprovided for the second mechanical speed and is sion part and the planetary gear is constructed to be arranged between the pumping wheel 61 in a special manner, thereby yielding a number of the converter and the planetary ring 60. This of shifting possibilities. More specifically, the coupling is made ineffective for the second mehydraulic transmission part consists of a torque chanical speed so that the pumping wheel will converter 50 and a hydraulic coupling 5| which not be driven rearwardly. The coupling may also have associated therewith a planetary transmisbe constructed as a plural disc coupling which sion 52 with double intermediate gears as a power furthermore makes it possible to shift a normal distributing drive and which also have associated l5 shiftable change gear instead of a planetary therewith a planetary drive 53 as an additional transmission. A further possibility consists in transmission. The motor shaft drives the carthe provision of a free wheel drive acting in rerier 55 for the two sets of intermediate gears verse direction (backward free wheel drive) 56 and 51. The sun wheel 58 meshing with the through which the pumping wheel during the set of smaller intermediate gears is connected driving conditions referred to will automatically with the transmission shaft 59, and the gear ring detach itself from the planetary ring.

60 meshing with the other set of the interme- Instead of a shiftable or free wheel coupling, diate gears 51 is connected with the hollow shaft also a device for emptying the converter may be which carries the converter pumping wheel 6| provided so that the free wheel coupling 85 may and the coupling wheel 62. The turbine wheel be omitted.

63 of the converter and the turbine wheel 64 of In some instances, it may also be desirable to the coupling are rigidly connected with each be able to make the guiding apparatus or reacother and are associated through a free wheel tor l1 inefiective. To this end, a brake 18 may coupling 65 with the transmission shaft 59. The be provided adapted selectively to hold the guidadditional transmission 53 consists of the planeing apparatus 11 stationary or to allow rotation tary ring 66 connected to the transmission shaft, of said guiding apparatus. of the carrier connected to the output shaft 61 In view of its numerous shifting possibilities the for the double intermediate gears of which latter transmission described in connection with Figure one set of gears 68 meshes with a sun wheel 69 5 is of part u advantage fo Veh cl s under adapted to be braked for forward driving, while high load. It is, of course, understood that if less the other set of intermediate gears 10 meshes requirements are to be met, some of the devices with a planetary ring H adapted to be braked referred to may be omitted. It should be borne for rearward driving. By providing a sun wheel in mind that with the arrangement of the dis- 15 meshing with the smaller intermediate gears tributor-planetary transmission referred to 10 and by braking the brake disc I6 connected above together with a single hydraulic circuit, to sun wheel 15, a further low forward speed can and a single add n drive merely for the idling be obtained. For idling; all brakes are released. d rearward Speed, there e avai ab e for the The arrangement is such that in the planetar forward as well as the rearward drive; a first hytransmission 52 the planetary ring 60 may b draulic speed with power distribution, a second braked by means of a. br k 12 hil th plane slightly increased mechanical speed, and a third tary ring 13 meshing with the intermediate gears greatly increased mechanical Speed. 56 may be braked by m ns f b k 14 Referring now to Figure 6, the structure dis- For starting, first only the forward brake '56 of closed therein comp a P p W el 80 0f the additional transmission is applied, whereas a Converter Which W n co ast to the emvthe four other brakes are released, Thus, a conbodiments Of Figures 1 t0 5, is connected with the verter operation with power distribution is 010- n Wh l Ella, whereas the transmission shaft tained. By changing the filling from the con- 3! is Connected W the Planetary ring verter "5D to the coupling 5! a hydraulic coupling carrier 83 driven by the motor shaft extends speed with power distribution will be obtained. around the outside of the planetary transmission. Then th brake 12 is applied, so t t t t As a result thereof, the distributing drive will mission shaft 59 will be driven with increased have a transmission ratio u of less than 1. The speed. As a result thereof the turbine wheels of p p W e Bil m y again, by means of a brake the coupling and of the converter will operatively at, be held stationary while the turbine wheel detach themselves from the shaft through the 85 may be drivingly detached from the transfree wheel drive. Consequently a purely memission shaft by me of free Wheel Coupling chanical speed will be obtained with a trans- 8B. The additional transmission 81 isatwo plane mission ratio corresponding to the transmission planetary transmission having its sun wheel 88 ratio in the planetary transmission (55/51/53) mounted on the driving shaft while the sun wheel By releasing the brake 12 and applying the brake 5k) is rotatably mounted on the output shaft 89. 14, a further mechanical speed with increased The carrier for the intermediate gears m y e transmission ratio will be obtained. With this held stationary by means of a brake 91 while transmission, the application of which is by no t e planetary ring meshing W One Of the t means limited to street vehicles but which may 0f t rm e ar may b held stationary by also be advantageously applied in particular for a brake 92. The planetary ring 93 meshing with power railroad cars and locomotives, two hythe other set of intermediate gears is adapted by draulic and two mechanical speeds are availmeans of a jaw coupling box 94; to be coupled able for forward as well as for backward driving. with the output shaft so as to rotate therewith. 1 These speeds may be doubled for forward driv- The said jaw coupling box Sill also serves for coning by changing the brakes H and 16. The nesting the output shaft with the sun wheel 90 shifting from the first to the second hydraulic while simultaneously connecting the planetary 13 ring andthe sun wheel (direct speed). A further brake 93a is provided for maintaining the planetary ring 93 stationary.

from the drawing that the arrangement disclosed therein comprises a planetary gear transmission with bevel gears. This gear transmission comprises a carrier [8i connected with the motor or input shaft I82. Of the two sun wheels pertaining to this gear transmission, the sun wheel K83 is connected with the output shaft I89, while the other sun wheel I86 is connected with the pumping wheel l8? and the brake drum I88. The output shaft N39 is connected with the turbine wheel I85 via a free wheel drive I84.

The arrangement according to FigurelO likewise employs a planetary transmission with bevel gears. However, in contrast to the structure of Figure 9, Figure shows a carrier Zlllsupporting two sets of different size intermediate gears 2H and N2, of which the gears 2H mesh with the sun wheel 213, while the gears 2l2 mesh With the sun wheel 214. The sun'wheel M3 is mounted on theoutput shaft 2|5 which in its turn via. a free wheel drive 2H5 is connected with the turbine wheel H1. The bevel gear 2| 4 drives the shaft 218 which latter has connected thereto the brake drum 2H) and the pumping wheel 220.

With the transmission according to Figure 9, the speed ratio u equals 1, whereas the speed ratio is greater than 1 with the transmission according to Figure 10. By using other combinations, the arrangement according to Figure I!) also makes possible a speed transmission ratio it less than 1.

Referring now to Figure 11, the transmission diagrammatically illustrated in this figure illustrates an arrangement referred to in connecto which only one hydraulic circuit and one plural disc coupling 95 is employed for connect ing the sun wheel 96 of the distributing drive 14 with the input shaft. As a special featurait chanical speeds is desired, the converter will be emptied. r

If the distributing drive cannot be coupled through, in other words if the coupling is missing, the hydraulic power transmission path may be interrupted withlthe converter remainsion according to WhlCh the pumping wheel I00 is connected with a sun wheel l0! while the output shaft N32 is connected with the carrier I03 for the intermediate gears. This carrier is arranged intermediate the two sets of intermediate gears. In addition to the said two sets there is provided a further set of intermediate gears we having associated therewith a sun Wheel 35 adapted to be held stationary by a The pumping wheel brake I06 and the brake it! for the sun wheel H25 are so con- By applying the brake pertaining to the sun wheel the rearward speed will be made effective.

Figure 13 shows a further modification of a two plane distributing planetary drive which is driven through a sun wheel Hi]. The smaller Sun Wheel ill is connected with the output shaft tionary. The output shaft will be driven purely mechanically through the planetary transmission. The turbine wheel M4 by means of free wheel drive [it detaches itself from the output shaft. When shifting to the next speed with greater transmission ratio, the brake 8a is ther speed with still greater transmission ratio can be obtained by applying the brake IIBa pertaining to the carrier for the intermediate gears while releasing the brake IISa.

As mentioned before, the embodiment shown in Figures 14 to 24 of the present invention differ from the embodiments illustrated in Figures 1 to 13 in that not the hydraulic transmission branch but the mechanical transmission branch of the differential drive is adapted to be made ineffective. The operation of such a drive may be described in connection with Figure 14.

The motor shaft I20 drives the carrier I2I for the intermediate gears I22 which latter mesh with the sun wheel I23 and the planetary gear The sun wheel I23 is rigidly connected shaft I30 with the pumping the planetary gear ring I24 via a free wheel coupling I25 is connected with the output shaft I26 which latter has keyed thereto the turbine wheel I32. The planetary gear ring I24 is adapted to be held stationary by means of a brake I21. The converter comprises a rotatable guiding apparatus I28 which is adapted during the operation of the converter to be held stationary by means of a brake I29. For starting purposes the guiding wheel of the converter is held stationary by applying the brake I20, and the power is transmitted to the output shaft hydraulically through the converter and partly mechanically through the planetary gear ring.

I24. through the hollow wheel I3I, whereas Then the brake I21 is applied and the brake I29 pertaining to the guiding wheel is released as a result of which the converter pumping wheel and through the hydraulic coupling action also the turbine wheel is driven with an increased speed. The output shaft is then able to rotate freely in the free wheel drive. The converter will during this working condition work as hydraulic coupling. While a torque converter with rotating guide wheel, at the same speed it has during the operation of the converter, will not have a sufficient transmitting capability, as is well known, inasmuch as it will have too great a slip and therefore is generally disadvantageous as mentioned above for this driving stage, according to the present invention after the guiding wheel has been detached, the pumping wheel and, therefore, also the turbine wheel are driven at increased speed. As a result thereof, the torque transmitted through the hydraulic circuit acting as a hydraulic coupling is increased. Thus, the converter, also when driven as a coupling, will have a sufficiently high transmitting capability with sufficient low slip. In contrast to the embodiments referred to above, in the last mentioned instance the shock absorbing features of hydraulics can be exploited with all speeds.

The embodiments shown in Figures 15, 16 and 17 are generally very similar to the device shown in Figure 14 and differ from the latter merely in some slight difference in arrangement of the various parts as will be clear from the drawings. According to Figure 15, the motor or input shaft is again connected with the carrier 22I of the planetary transmission, the sun wheel 222 of which drives the pumping wheel 223. The gear ring 224 is connected with the intermediate shaft 225 which at its rear end carries a brake drum 226. The turbine wheel 221 of the converter is connected with the gear 228 which latter is connected through a free wheel drive 220 with the intermediate shaft 225 and meshes with a gear 230 driving the output shaft 230a.

The embodiment according to Figure 16 differs from that of Figure 15 merely in that the connection of the intermediate shaft with the sun wheel and the planetary gear ring is reversed. In other words, according to Figure 16, the intermediate shaft 23I, instead of being connected to the gear ring, is connected to the sun wheel 232, while the pumping wheel 233, instead of being connected to the sun wheel, is connected to the gear ring 234. Also, in this embodiment, the intermediate shaft has connected thereto a brake drum 235.

According to the structure shown in Figure 11, the power distributing planetary transmission is constructed as a two plane planetary transmission. One sun wheel 236 is mounted on the input shaft, while the other sun wheel 231 is connected to the intermediate shaft 238 which also carries the brake drum 23 9. The gear carrier 246 is connected with the pumping wheel 242 by means of the hollow shaft MI. The turbine wheel 243 is connected with a gear 244 which in its turn is connected via a free wheel drive 245 with the intermediate shaft 238 and meshes with a gear 246 supported by the output shaft.

Referring now to Figure 18, the structure shown therein, comprises a planetary gear transmission I with double intermediate gears MI and I42 and an additional sun wheel I44 adapted to be held stationary by and a jaw free wheel coupling I48 are provided for making the mechanical transmission branch ineffective. The brake drum of the brake I45 is mounted on an intermediate shaft I41 which also carries the sun wheel I46. The coupling I48 is arranged between the shaft I41 and the turbine wheel I49 rigidly connected to the output shaft. The free wheel coupling I48 is adapted to be locked by means of a manually operable shifting sleeve I50 in a manner similar to that described in connection with Figure 5.

Figure 19 illustrates a transmission with a power distribution drive I including a carrier I63 for two sets of intermediate gears I6I, I62 respectively meshing with sun wheels I6Ia and I62a. The carrier I63 is arranged between the said two sets of intermediate gears. The additional transmission I64 again comprises three sets of intermediate gears I65, I66, I61, and three brakes I68, I69, I10. The brake IE8 is applied for the normal speed. The brake I60 is intended for the low speed, while the brake I16 is applied for obtaining a rearward speed. When idling, all three brakes are released. The sun wheel I1I of the intermediate planetary gear is connected with the transmission shaft I12 which latter also carries the planetary gear ring I13 of the first set. The planetary gear ring I14 of the intermediate set is connected with the carrier I15 of the first set and with the sun wheel I16 of the third set. The carrier I11 of the second set and the carrier I18 of the third set are connected with the output shaft. The sun wheel of the first set, the planetary gear of the second set, and the planetary gear ring of the third set are adapted to be held stationary by means of the three brakes I68, I69, I10 respectively. A brake I86 is provided for braking the carrier of the intermediate gears of the distributing transmission.

Figures 20, 21, 22 illustrate an arrangement of a hydraulic coupling provided in the hydraulic transmission branch, while Figure 23 shows a device the hydraulic transmission branch of which has arranged therein a hydraulic coupling and in addition thereto a converter without power distribution. Here, specifically, the hydraulic a brake I43. The brake I45 aeszeo'r part-of thestructure according to Figure. 20 inobtain the thirdspeed, itis necessary additionally cludes a hydraulic coupling 250 the pumping to apply the brake I93 and to release the guide Wheel25l of which is drivinglyconnected through wheel brake 209. This is a hydraulic coupling an intermediate shaft252 with thesmaller sun speed without power distribution. In this speed Whee1253 ofa two planeplanetarytransmission 5 also converter opera ion would be possible. In 5H0: The other sun wheel 254 is mounted on the order to obtain the fourthspeed, the coupling inputshaft, while the carrier 255-for the planesleeve 204 is moved toward the right so that it and is connected: through a free wheel drive: 258 the planetary gear ring 203 with the output shaft. with the turbine wheel'251 of the hydraulic couhis i a yd au ic C p Speed h different pling 250; transmission ratio.

Figure 21 illustrates .an arrangement inwhich In order to obtain therearward speed, itis the inputshaft 258aisadaptedby means of a merely necessary to apply the brake 200 (or if gear 258 to drive the carrier259 forthe intermedesired both brakes 200 and 289) and to move diate gears 259a; The gearring-ZSOofthe planethe coupling sleeve 2M toward the right. When tary transmission is connectedl'through. a free op at g atthe ldllng peed, 1 b akes ha e to" wheel drive 26! with the output shaft 263 which be released and the coupling sleeve 2M has to be latter also carries the turbine wheel 262 of the in its left or right hand position.

hydraulic coupling 501, The pumping wheel 264 As will be clear from the foregoing description, of coupling 50] isdrivingly connected with the the present invention is by no means limited to sun wheel 266 of the planetary transmissions via the parti ular con r ion h wn as mpl ahollow shaft 265. Furthermore; abrake 502 in the accompanying drawings, but also comis provided for braking the gear ring 260. prises any modifications within the scope of the The arrangement according to Figure 22 is appended claims. rathersimilar to that of Figure 21, however, the 25 What we claim is:

1. In combination, a hydraulic torque converter nected with the pumping wheel :zssa, while the i including a p mping Wheel and a turbine wheel wheel 269, transmission shaft, planetary gear means, includ- The structure shown in Figure 23, comprises a ing intermediate gears and in addition thereto torque converter 210, the pumping wheel 2?! of three further active elements, namely a-first sun which is directly connected to the input shaft wheel connected with the said input shaft; a car- 5ll5." The turbine wheel 272 of the converter 2m rier for said intermediate gears, and a second sun 2190f the two plane planetary geartransmission 40 one part of said planetary gear means, second 215 is mounted on the shaft-218 Whichhas also power conveying means arranged drivingly to mountedthereon a brake drum-280= The: shaft connect another part of said planetary gear 218 is connected with the shaft 509 through a means with the transmission shaft through the free wheel drive 211.- said Wheels of the hydraulic power-transmission The transmissionacc'ordingto Figure 24 -repre-- mechanism, coupling means arranged for cooper which isconnected- Wifih -the lmmp ng Wheel 92] 5 said transmission shaft, and braking means astherbrake 20B is provided forselectively braking ing speed of the other power conveying means, theplanetary carrier l99which latter carriesthe the-ratioofu to b i. e., the ratio of the drive intermediate-gear l9lofthis second set and the r ti of said planetary gearmeans to the speed intermed a gears 8 0 next The ratio between the said Wheels of said'torque conplan t r s r 21H mayb h ld s a ionary verter at the shifting point being in the range by' means of-brake- 202, Whereas the planetary f fr-0111,04 t 1.0,

s ar n 203 d p nd n th pos t f t 2; A ower transmission comprising in combishiftable coupling sleeveZM maybe coupled with nation, hydraulic power transmitting means in- By applying the brakes 200"and 209*and movranged drivingly to connect said transmission ing the coupling sleeve 204 toward the left, the shaft with one part of said first planetary gear ingflthe brake 202 the secondconverter speed with planetary gear means with the said transmission power distribution is made effective. In order to shaft through the said rotatable elements, coupling means arranged for cooperation with one of said power conveying means and operable to effect and interrupt the transmission of power from said input shaft through said last mentioned power conveying means to said transmission shaft, and braking means associated with that part of said first planetary gear means, which is connected to said last mentioned power conveying means, and operable to bring about interruption of the transmission of power through said last mentioned power conveying means, to thereby cause an increase in the driving speed of the other power conveying means, an output shaft, a second planetary gear means consisting of a first set, a second set and a third set of planetary gear transmissions, each of said sets comprising a planetary gear ring and intermediate gears respectively meshing therewith, said first and said third sets also comprising a sun wheel, the intermediate gears of said first and said second sets being rigidly interconnected, a carrier common to said last mentioned intermediate gears for supporting the same, said carrier being rigidly connected with th planetary ring of said third set, the sun wheel of said last mentioned set being keyed to said transmission shaft, a second carrier carrying the intermediate gears of said last mentioned third set and being drivingly connected with said output shaft and with the planetary ring of said second set, and braking means respectively associated with the sun wheel and the planetary ring of the first set and with the planetary ring of said third set which is connected with the carrier of the first and second sets, said braking means being arranged for selectively holding stationary said last mentioned sun wheel and said last mentioned two gear rings respectively.

,3. A power transmission comprising in combination, a hydraulic torque converter including rotatable elements arranged, when actuated, to rotate in one and the same direction, a power input shaft, planetary gear means drivingly connected to said input shaft and including intermediate gears and in addition, three further active elements, namely, a first sun wheel connected with said input shaft, a carrier for said intermediate gears and a second sun wheel, said intermediate gears consisting of two sets of gears arranged side-by-side and respectively meshing with said first and second sun wheels, an output shaft, first power conveying means arranged drivingly to connect said output shaft with one part of said planetary gear means, second power conveying means arranged drivingly to connect another part of said planetary gear means with the output shaft through the hydraulic torque converter, coupling means arranged for cooperation with one of said power conveying means and operable to effect and interrupt the transmission of power from said input shaft through said one of said power conveying means to said output shaft, and braking means associated with that part of said planetary gear means which is connected to said one of said power conveying means, said braking means being operable to bring about interruption of the transmission of power through said one of said power conveying means, to thereby cause an increase in the driving speed of the other power conveying means, the transmission ratio of u to c,,, i. e., the tranmission ratio of the planetary gear means to the speed ratio at the shifting point in the hydraulic power transmitting means being within the range of 0.4 to 1.0.

4. A power transmission comprising in combination, hydraulic power transmitting means including rotatable elements arranged to rotate in one and the same direction in operation, a power input shaft, first planetary gear means drivingly connected to said input shaft, a transmission shaft, first power conveying means arranged drivingly to connect said transmission shaft with one part of said first planetary gear means, second power conveying means to drivingly connect another part of said first gear means with the transmission shaft through the said rotatable elements, an output shaft, second planetary gear means drivingly interconnecting said transmission shaft and said output shaft, coupling means arranged for cooperation with one of said power conveying means and operable to effect and interrupt the transmission of power from said input shaft through said last mentioned power conveying means to said transmission shaft, brake means associated with one of said power conveying means and operable to interrupt the transmission of power therethrough, said second planetary gear means comprising a plurality of sets of planetary gears, including sun gears, one of which is connected with the transmission shaft, the carrier for the planet gears of the same said set being connected with the output shaft, and the ring gear for the same said set being provided with brake means, another of said sets also comprising a sun gear, intermediate gears and a ring gear, and brakes for said last mentioned sun and ring gears, and a carrier for said last mentioned intermediate gears being connected with the first mentioned of said ring gears.

5. An arrangement as set forth in claim 4, in which still another planetary gear set is included in said secondary planetary gear means including a ring gear connected with said output shaft and planet gears running thereon and connected with the intermediate gears of the second mentioned planetary gear set of said second planetary gear means.

6. In combination, a hydraulic power trans-- mission including a pumping wheel and a turbine wheel arranged to rotate in one and the same direction in'operation, an input shaft, a transmission shaft, a power output shaft, planetary gear means including a sun gear connected with said input shaft, another sun gear connected with said transmission shaft, and compound planet gears meshing with said sun gears, a carrier for said planet gears connected with said pumping wheel, brake means for braking said carrier, clutch means between said turbine wheel and said transmission shaft for coupling said turbine wheel to said transmission shaft in one direction of relative rotation therebetween, and for releasing the turbine wheel from the transmission shaft in the opposite direction of relative rotation therebetween, and second planetary gear means interconnecting said transmission shaft with said output shaft.

7. In combination, a hydraulic power transmission including a pumping wheel and a turbine wheel arranged to rotate in one and the same direction in operation, an input shaft, a transmission shaft, a power output shaft, planetary gear means including a sun gear connected with said first input shaft, another sun gear connected with said transmission shaft, and compound planet gears meshing with said sun gears, a carrier for said planet gears connected with said pumping wheel, brake means for braking said carrier, clutch means between said turbine wheel and said transmission shaft for coupling said turbine wheel to said transmission shaft in one sun and ring gears of the said additional set, and a carrier for said planet gears connected with the ring gear of the first mentioned set of planet gears of said second planetary gear means.

9. An arrangement as called for in claim 8 in the same, said carrier being rigidly connected with the planetary ring of said third set, the sun wheel of said last-mentioned set being keyed to said second shaft, 2. second carrier carrying the intermediate gears of said last-mentioned third set and being drivingly connected with said output shaft and with the planetary ring of said second set, and braking means respectively asso- 12. A power transmission according to claim 2 in which the said transmission ratio of u to is closer to 0.4 for relatively small steps between two successive speeds and closer to 1.0 for larger steps between two successive speeds.

mediate gears of said first and second sets being rigidly interconnected, a carrier common to said last-mentioned intermediate gears for supporting with the planetary ring of said third set, the sun wheel of said last-mentioned set being keyed to mentioned two gear rings respectively.

14. A power transmission as claimed in claim 1 with the coupling means arranged for cooperation with one of said power conveying means consisting of an overrunning clutch.

15. A power transmission as claimed in claim 2 with the coupling means arranged for cooperation with one of said power conveying means consisting of an overrunning clutch.

16. A power transmission as claimed in claim 3 With the coupling means arranged for cooperation with one of said power conveying means consisting of an overrunning clutch.

ReferencesCited in the file of this patent UNITED STATES PATENTS.

Number Name Date 2,135,282 Fottinger Nov. 1, 1938 2,147,528 Fottinger Feb. 14, 1939 2,176,105 Schneider Oct, 17, 1939 2,232,101 De Turk Feb. 18, 1941 2,283,759 Pollard May 19, 1942 2,293,767 Salerni Aug. 25, 1942 2,301,451 Pollard Nov. 10, 1942 2,364,448 Jandasek Dec. 5, 1944 2,365,879 Jandasek Dec. 26, 1944 2,383,981 Lysholm Sept. 4, 1945 2,40 ,164 Kelbel June 18, 1946 2,416,129 Swift Feb. '18, 1947 FOREIGN PATENTS Number Country Date 384,816 Great Britain Dec. 15, 1932 450,953 Great Britain Aug. 24, 1935 

